Burosumab for Fibrous Dysplasia

Overseen By Olivia J de Jong, C.R.N.P.

Age: Any Age

Sex: Any

Trial Phase: Phase 2

Sponsor: National Institute of Dental and Craniofacial Research (NIDCR)

Must not be taking: Investigational drugs

Disqualifiers: Pregnancy, Severe renal impairment, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 4

Duration: 48 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a drug called burosumab to determine its effectiveness for individuals with fibrous dysplasia (FD), a condition that weakens bones and can cause deformities and fractures. The trial focuses on those with FD who also have low blood phosphate levels, which can further weaken bones. Participants will self-inject burosumab at home and visit the National Institutes of Health (NIH) for tests and assessments to monitor their health and the treatment's effects. The trial seeks participants diagnosed with FD and low blood phosphate levels. As a Phase 2 trial, the research measures the treatment's effectiveness in an initial, smaller group of people.

Will I have to stop taking my current medications?

The trial information does not specify if you need to stop taking your current medications. However, you cannot participate if you have taken another investigational drug or burosumab within 30 days before screening.

Is there any evidence suggesting that burosumab is likely to be safe for humans?

Research shows that specific safety information for using burosumab in people with fibrous dysplasia (FD) is not yet available. However, burosumab has approval for treating other conditions involving low phosphate levels in the blood. In studies for those conditions, most participants tolerated it well, with some reporting mild side effects like injection site reactions, headaches, and joint pain.

This is a phase 2 study, indicating that burosumab has already undergone basic safety testing. This phase focuses on assessing its effectiveness and monitoring for any side effects. Prospective participants should discuss potential risks and benefits with the study team before joining the clinical trial. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Burosumab is unique because it targets a specific pathway involved in bone metabolism by inhibiting the activity of fibroblast growth factor 23 (FGF23). Unlike standard treatments for fibrous dysplasia, which mainly focus on managing symptoms with medications like bisphosphonates, Burosumab addresses the underlying cause of bone deformities. Researchers are excited about Burosumab because it has the potential to directly improve bone health and reduce complications by targeting the hormone that disrupts normal bone formation. This approach could lead to more effective management of the condition with fewer side effects.

What evidence suggests that burosumab might be an effective treatment for fibrous dysplasia?

Research shows that burosumab, the treatment under study in this trial, can improve bone health in people with fibrous dysplasia (FD). Studies have found that it reduces bone pain, increases muscle strength, and makes walking easier. Burosumab raises low phosphate levels in the blood, a common issue in people with FD. This increase strengthens bones and lowers fracture risk. Although limited information exists specifically for adults with FD, early results are promising for improving bone conditions in similar disorders. So far, these studies have not shown any major side effects from the treatment. ^{1 2 3 4 6}

Who Is on the Research Team?

Alison M Boyce, M.D.

Principal Investigator

National Institute of Dental and Craniofacial Research (NIDCR)

Are You a Good Fit for This Trial?

This trial is for people of any age over 1 year with fibrous dysplasia (FD) and low blood phosphate levels. Participants must be able to self-inject the study drug, burosumab, agree to use effective contraception if of reproductive potential, and have a minimum body weight of 7.5 kg. Those who are pregnant or lactating, have severe kidney issues, or have used burosumab or other investigational drugs recently cannot join.

Inclusion Criteria

I have been diagnosed with fibrous dysplasia.

I am a male sterilized at least 6 months ago, or my only partner is a vasectomized male.

-- Placement of an intrauterine device (IUD) or intrauterine system (IUS)

Exclusion Criteria

Have any condition which in the opinion of the PI could present a concern for subject safety or difficulty with data interpretation

I have severe kidney problems or am in the final stage of kidney disease.

Pregnancy or lactation

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive burosumab injections to normalize serum phosphate levels, with NIH visits every 16 weeks for assessments

48 weeks

3 visits (in-person at NIH), monthly home injections

Follow-up

Participants are monitored for safety and effectiveness after treatment, including additional follow-up for children

4-6 weeks

1 visit (in-person for children), local lab visits for blood and urine tests

What Are the Treatments Tested in This Trial?

Interventions

• Burosumab

Trial Overview The trial tests burosumab in individuals with FD who suffer from weak bones due to low phosphate levels. Over 48 weeks, participants will visit NIH three times for extensive testing including physical exams and bone scans while self-administering injections at home regularly under telehealth guidance.

How Is the Trial Designed?

Group I: Treatment Experimental Treatment 1 Intervention

Patients receiving treatment

Who Is Running the Clinical Trial?

National Institute of Dental and Craniofacial Research (NIDCR)

Lead Sponsor

Trials

312

Recruited

853,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8272883/

Burosumab Treatment for Fibrous Dysplasia - PMC This was accompanied by an encouraging clinical response, including decreased bone pain, improved muscle strength, and improved ambulation. No adverse effects ...

2. clinicaltrials.gov clinicaltrials.gov/study/NCT05509595

Study Details | NCT05509595 | Burosumab for Fibroblast ... Study Overview · Evaluate the efficacy of burosumab to normalize serum phosphate levels in subjects with FD and FGF23-mediated hypophosphatemia at 24 weeks.

3. academic.oup.com academic.oup.com/jbmrplus/article/9/9/ziaf125/8212267

Burosumab treatment for fibroblast growth factor-23 ... To date, there is no evidence on the efficacy and safety of burosumab treatment in adults with fibrous dysplasia/MAS. This is, thus, the first report.

4. frontiersin.org frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2025.1577734/full

Use of burosumab in McCune Albright syndrome: case ... Burosumab showed beneficial effects on bone tissue metabolisms in our patient without significant adverse effects but did not change FD course.

5. fcd.mcw.edu fcd.mcw.edu/?search/showPublication/id/1552157

Burosumab treatment for fibrous dysplasia. Bone 2021 Sep This was accompanied by an encouraging clinical response, including decreased bone pain, improved muscle strength, and improved ambulation. No ...

6. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1521690X23001008

9 Burosumab: Current status and future prospects Data from phase 2 and 3 trials report overall safety and efficacy and Burosumab ... Gladding et al. Burosumab treatment for fibrous dysplasia. Bone. (2021). C ...